Lubricating composition



Patented Apr; 4, 1939 UNITED STATES 'LUBRICATING COMPOSITION Carl F. Prutton, Cleveland Heights, )hio assignor, by mesneassignments; to The Lubri-Zol Development Corporation, Cleveland, Ohio, a

corporation of Delaware No Drawing. Application April 21,

Serial No. 203,439

8 Claims. (Cl. 87- -9) ing composition characterized by being capable of withstanding extreme unit pressures between the bearing surfaces which the same is called upon'to lubricate, without the disadvantages of instability and gum-forming tendencies whichcharacterize similar lubricating compositions .now

commonly available. 10 This application is a continuation in part of copending application Serial No. 737,070, filed July 26, 1934.

By extreme pressures, as referred to above, is meant pressures of or in excess of 10,000pounds per square inch, such pressures now being commonly encountered in hypoid gears, bearings,

contact surfaces of cylinders and piston rings in internal combustion engines, and -many other I points. Such pressures tend to cause the rupture l of the continuous thick'film of lubricant-which separates bearing surfaces-under more moderate conditions. A- region of thin-film'lubrication results which is also sometimes described as boundary lubrication.

It is a principal object of this invention", there-' fore to provide a method of lubricating and. a

lubricating composition which will operate under conditions of extreme pressure to prevent seizure between the relatively moving metallic surfaces to and which may be so employed without danger of, deleterious eiTect upon the parts lubricated.

Other objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and re- 35 lated ends, said invention, then, consists of the" means hereinafter fully described and'particularly pointed out in the claims; the following description setting forth in detail cert'ain' approved combinations of ingredients embodying my in- 40 vention, such disclosed-means constituting, however, but certain of various forms in which the principle of the invention may be used.

Broadly stated, this inventioncomprises a method of lubricating and a lubricating compo- 425 sition wherein a minor proportion of a halogenbearing dibenzyl disulphide is employed in conjunction with a hydrocarbon oil.

While for certain specialized uses the halogenbearing dibenzyl disulphide may be employed as 50 the sole lubricant this invention contemplates that in general it will be employed as an addition agent to mineral lubricating oils in amounts ranging from about .2% to about 20% by weight, based on the amount of mineral oil. For most pur- 55 poses and under most conditions from about 1% The present invention relates, as indicated, to lubrication and moreparticularly toa lubricatto about 5% of the addition agent will be found; to be. sufficient to accomplish theend desired although for certain uses and conditions amounts up to 10% and even 20% are occasionally prefer-red. The final-productshould contain atleast 5 2% of the addition agent in order that it may exhibit suificient extreme pressure properties to be commercially feasible. i

While the oil base is-referred. to above as a mineral lubricating oil',--i t is to be understood that. 10. 1

any other suitable hydrocarbon lubricating oil, whether :naturally occurringgor synthetic, may. be 'employed 'as the :oil base.

It is also within the contemplation of this invention to provide the addition agent in the form 16 of aconcentrateinv a suitable oil, said oil containing rather large percentages of the addition agent. Such concentrates are employed for future blending with a lubricating oil in the proportions desired for the particular conditions of n use.

It is believed that under conditions of extreme pressure'the addition agent reacts chemically or physico-chemically with the metallic surfaces to form a non-fluxing surface which will not seize 25 or score." This inventionis notintended to be limitedfhowever," by any particular. theory or explanation of the action upon' the metallic surfaces. r I 1 All of the various halogens are effective when employed in accordance with the present invention but chlorine is generally preferred inasmuch as itis the ieast expensive and one of the most effective of the halogens. Bromine. and fluorine are more expensive andthe latteris relatively difficult to handle but they are each usable in accordance with this invention. Iodine'is not ,so readily obtainable as the other halogens andis quite expensive but it also is satisfactory in providing eiiective addition agents. It should also be noted that two or more different halogensmay. bewpresent in. the, same molecule. The bromchlors-and fluorinated chlorine or bromine' compounds give especially satisfactory results.

When a chlorine-bearing dibenzyl disulphide is employed as the addition agent, it will preferably. contain from about 10%fto about 60% chlorine although both larger and smaller percentages may Occasionally be preferred.

Halogembearing dibenzyl disulphide is a particularly satisfactory addition agent to. mineral oils because, in addition to its effectiveness, it is Percent chlor-dibenzyl pressures but also greatly increases the solubility of the addition agent in mineral oils.

f the halogen-bearing dibenzyl disulphidcs, di (chlor-benzyl) disulphide, disclosed in 00- pending application Serial Number 737,070, has proven particularly eiliective and satisfactory. This compound may be prepared in the manner described in my co-pending application Serial Number 193,960, filed March 4, 1938.

When still greater resistance to extreme-pressure conditions is desired than that afforded by the addition agent of this invention alone it may often be found advantageous to employ a small amount of a separate organic halogen compound which will cooperate with the addition agent of this invention to increase the film strength of the lubricant (as indicated on the Almen machine) to a degree greater than the sum of the effects lit either addition agent when used alone. While the lubricating compositions which have been described herein as illustrating one embodiment or .the invention have been generally referred to as oils, i. e., liquids, this invention is, however, also especially applicable to the solid and semi-solid types of lubricants commonly referred to in the trade as greases, bodied oils, etc., and which may contain soaps such as sodium, calcium, lead, and aluminum naphthenates, stearates, and oleates. The following table shows the results obtained when testing various percentages of chlor-dibenzyl disulphide in an SAE 160 lubricating oil on the Almen machine:-

Percent chlor-dibenzyl Almen (pounds) On a modification of the Faville-Levalley machine employing a flat block the following results were obtained:--

Faville-Levalley disulphide dial readin 2+1% dibenzyl disulphide 2375 Plain oil (SAE 160) 750 The two tables above given clearly show the eflectiveness of even small percentages of the addition agent.

While mineral oil generally is the principal ingredient ot the lubricant, it is not essential that it be the only ingredient other than the addition agent, provided that there be no additional ingredient which is incompatible with such addition agent. It is within the contemplation 01 this invention to include, it necessary or desirable, such other addition agents as are commonly added to improve the viscosity index or cold test 0! the lubricant and a lubricatingcomposition according to this invention which also has a separate oiliness increasing agent has been found to be especially effective.

explained, change being made as regards the The terms halogen-bearing and chlorinebearing" as employed in the appended claims is obviously intended to mean halogen, or more specifically chlorine, in chemical combination.

Other modes of applying the principle of my invention may be employed instead of the one composition and method disclosed, provided the ingredients or steps'stated by any of the following claims or the equivalent of such stated ingredients or steps be employed.

I therefore particularly point out and distinctly claim as my invention:-

1. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of a minor proportion of a halogenbearing dibenzyl disulphide.

2. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of from an efiective amount to 20% of a halogen-bearing dibenzyl disulphide.

3. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of from about .2% to about 10% of a halogen-bearing dibenzyl disulphide.

4. An extreme pressurelubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of from about 1% to about 5% of a halogen-bearing dibenzyl disulphide.

5. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of a minor proportion of a chlorine-bearing dibenzyl disulphide.

6. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of from an efiective amount to 20% of a chlorine-bearing dibenzyl disulphide.

7. An extreme pressure lubricating composition comprising a major proportion of lubricating oil the film strength of which has been substantially increased by the inclusion therein of from about 2% to about of a chlorine-bearing dibenzyl disulphide.

8. An extreme pressure lubricating composition comprising a major proportionof lubricating oil the film strength of which has beensubstantially increased by the inclusion therein of from about 1% to about 5% of a chlorine-bearing dibenzyl disulphide.

CARL F. PRU'I'ION.

CERTIFICATE OF CORRECTION.

Patent No. 2,155,) 82. April h, 1959.

CARL F. PRUTTON.

It ishereby certified that error appears' in the printed specification of theabove numberedpatent requiring correction as follows: Page 2, second column, line 5, strike out the words "explained, change being made as regards the" and insert thesame after the word "one" in'line 11; and that the said Letters Patent'should be read with this correction therein that the same may conform to the record of the/case in the Patent Office.

Signed and sealed this 25rd day of May, A. D. 1959.

Henry Van Arsdale (Seal) Acting Commissioner of Patents. 

